Variables and References

[Aytek Yüksel]

Hi,

I'm new to ruby. Trying to understand how variables hold references to
objects.
I wrote some simple example for this:

##
# Trying to observ person1 and person2 are aliases.
# (they references the same object)

person1 = "Tim"
person2 = person1
person2[0] = "s" # This changes both

puts person1
puts person2

# Produces:
#
# Tim
# sim

# Second part
person3 = "Tim"
person4 = person3
person4 = "s"

puts person3
puts person4

# Produces:
#
# Tim
# s

I expect that the second part will print:
s # not Tim
s

What's the reason that when I assign something to person3, person4
doesn't change although they are aliases (or aren't they?)

Thanks,
Aytek

 

[dblack]

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Hi --

What's the reason that when I assign something to person3, person4
doesn't change although they are aliases (or aren't they?)

When you do an assignment, you wipe out that variable's previous
reference, if any. You're re-using the identifier person3, and thus
breaking its connection with the object that both it and person4
referred to.


David

--=20
Q. What's a good holiday present for the serious Rails developer?
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[Aytek Yüksel]

I did a silly mistake.
Thank you Paul and David for your great answers.

Aytek